Polyionenes
(Ion-Containing Polymers)

Properties and Applications

Polyionenes¹ are special polyelectrolytes that have onium groups such as quarternary ammonium in the polymer backbone as opposed to charged pendant groups. They are typically synthesized through a Menshutkin reaction of ditertiary amines and alkyl dihalides. A large number of dihalides and ditertiary amines are commercially available which permits the synthesis of a large number of well-defined polyionenes from relative cheap starting materials. 

Like ordinary cationic polyelectrolytes, polyionenes find applications as flocculation agents in waste water treatment, paper making, etc.³ They are very effective due to the high charge density. Other (potential) uses include biochemical and medical applications such as antimicrobials agents.⁴ In comparison to many low-molecular weight biocides, polymeric antimicrobial agents based on quaternary ammonium groups exhibited higher antimicrobial activity. Many ionenes also exhibit low toxicity and improved chemical stability.⁵ Principally polyionenes are expected to have similar uses as ordinary cationic polyelectrolytes.

¹The term "ionene", which is the abbreviation for ionic amine, was coined by Rembaum et al. in 1968^2
2A. Rembaum, W. Baumgartner, & A. Eisenberg, J. Poly. Sci. Part B: Poly. Let., 6(3), 159-171 (1968)
³N, Bicak, U. Tunca, Polymer Bulletin 43, 477–483 (2000)
⁴Xiang Xu et al., J. Mater. Sci. 48, 1162-1171 (2013)